1. Field of the Invention
The present invention relates generally to bars used to support the cutting chain of a chainsaw, and more specifically to an anti-pinch chainsaw bar assembly designed to facilitate extraction of a chainsaw bar bound or pinched during the cutting of timber.
2. Description of the Related Art
Chainsaws are typically used to fell timber and to trim branches from trees. Afterwards, the trunk and branches are typically cut into smaller sections for ease of handling and use as firewood. While cutting timber or other material with a chainsaw, care should be taken to avoid pinching or binding the chainsaw bar within the gap formed by the cut. Nevertheless, binding may occur due to unexpected material movement and, in particular, may be difficult to avoid when cutting limb wood which is subject to twisting, due to wind and to movement under force of gravity, including rotational forces exerted upon the limb from associated branches. In addition, limb wood is known to contain internal forces that may be released as the limb is cut causing the gap to close upon the bar.
Since the bar generally has opposing flat sides that each typically present a relatively large surface area, the bar may be quite difficult to remove from the gap when binding occurs. To remove the bar, it may be necessary to reposition the material being cut or to pry the gap open using separating mechanisms. While these solutions may be time-consuming but useful when cutting timber to length on the ground, they may not be practical when binding occurs within a large branch still attached to the trunk and suspended high above ground.
It would be advantageous, therefore, to have a chainsaw with a bar adapted to be more readily withdrawn from material being cut even when pinched or bound.